CIRCUIT DE CONVERSION DE TENSION CONTINUE, PROCÉDÉ DE CONVERSION DE TENSION CONTINUE ET DISPOSITIF D'AFFICHAGE À CRISTAUX LIQUIDES

摘要

Disclosed are a DC voltage conversion circuit, a DC voltage conversion method and a liquid crystal display device. The circuit comprises: a boost circuit 1, a charge pump circuit 2, and a control circuit 3; the control circuit is additionally provided with a first current detection module 201, a second current detection module 202, and an AND gate Y1; a first current I1 in the boost circuit 1 is detected by means of the first current detection module 201, and a high level or a low level is supplied to a first input end of the AND gate Y1 according to the magnitude of the first current 11; a second current I2 in the charge pump circuit 2 is detected by means of the second current detection module 202, and a high level or a low level is supplied to a second input end of the AND gate Y1 according to the magnitude of the second current I2; when the first current I1 is relatively small and the second current I2 is relatively large, namely the boost circuit 1 is at a light load and the charge pump circuit 2 is at a heavy load, a level at the output end of the AND gate Y1 is used to control a switch module 301 to increase the switch frequency of the switch module 301, so that the normal work of the charge pump circuit 2 is ensured, and the stability of the VGH voltage is improved.